Method and construction of a ski boot

ABSTRACT

Footwear, such as a ski boot, include interfitting inner and outer shells. The shells are divided into corresponding toe and heel sections, hinged together for coordinate opening to permit foot entry from the rear of the boot. The inner shells are fabricated with a resilient, custom-fit lining formed to conform precisely to the contours of the wearer&#39;&#39;s foot. Removable inner soles and inner heels of adjustable height are provided with one embodiment of the inner shell. In fabricating the custom-fit shells, a liquid lining composition of uncured elastomer is injected into the shells, filling voids around the wearer&#39;&#39;s feet; and permitted to cure before the feet are removed. Stockings of polyethylene film can be placed over the feet before the customfitting operation to prevent the lining composition from adhering to the feet and to permit easy separation of the shells, when finished.

United States Patent Anderson Feb. 8, 1972 [72] Inventor: Roland M.Anderson, 1616 S.W. Sunset Blvd., Portland, Oreg. 97201 [22] Filed:Mar.2, 1970 [21] Appl.No.: 15,375

[52] US. Cl. ..36/2.5 AL, 12/142 P 3,521,385 7/1970 Dalebout ..36/2.5 AL

Primary Examiner-Patrick D. Lawson Attorneyl(olisch & Hartwell [57]ABSTRACT Footwear, such as a ski boot, include interfitting inner andouter shells. The shells are divided into corresponding toe and heelsections, hinged together for coordinate opening to permit foot entryfrom the rear of the boot. The inner shells are fabricated with aresilient, custom-fit lining formed to conform precisely to the contoursof the wearers foot. Removable inner soles and inner heels of adjustableheight are provided with one embodiment of the inner shell. Infabricating the custom-fit shells, a liquid lining composition ofuncured elastomer is injected into the shells, filling voids around thewearers feet; and pennitted to cure before the feet are removed.Stockings of polyethylene film can be placed over the feet before thecustom-fitting operation to prevent the lining composition from adheringto the feet and to permit easy separation of the shells, when finished.

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saw a or 2 Fi J 7 RolandM.Hnderson IN VEN TOR METHOD AND CONSTRUCTION OFA SKI BOOT BACKGROUND OF THE INVENTION The present invention concernsimproved footwear which are custom-fit in the sense that the footwearhave an inner surface formed to conform precisely to the contours of anindividual wearers feet. More particularly, the invention relates tocustom-fit footwear comprising interfitting inner and outer memberswhich are adapted for quick easy entry of the wearers feet from the rearof the footwear. The invention also concerns an improved method ofmanufacture of such footwear which is especially suited for theproduction of certain athletic footwear such as ski boots or skateuppers.

Satisfactory custom-fit footwear should have resilient linings whichconform precisely to the contours of an individual wearers feet, arecomfortable to wear, and yet are sufiiciently firm to provide adequatesupport and restraint to the feet. Particularly where athletic footwearare concerned, effective custom-fitting is desirable. Thus, it isessential that ski boots or skate uppers have a comfortable, yet snugfit so that the athletes movements are directly translated intocorresponding equipment movements and not lost through shifting of thefeet within the boots. In the case of ski boots, for example, properedge control of the skis which is essential to controlled skiing canonly be achieved through boots which respond directly to movements ofthe wearer without any slippage.

Numerous lacing and strap arrangements have been suggested inconjunction with padded footwear to provide satisfactory fitting.However, most such arrangements do not invariably produce a satisfactoryfit and are otherwise objectionable for various reasons.

For example, systems utilizing special lacings and straps do not produceexactly the same fit each time the footwear is put on, and ofteninterfere with circulation even when appreciable care is exercised bythe wearer. lftight enough to transmit foot movements accurately, lacedboots often hurt. Furthermore, the use of such lacing systems is usuallytime-consuming and energy-consuming and, therefore, quite undesirable inconjunction with athletic footwear.

On the other hand, custom-fit footwear provided with insertable pads orperformed pads are not completely satisfactory in view of the difficultyin determining accurately the proper size and contour of the pads. Also,such footwear are usually ditficult to put on, cumbersome to wear, andtend to hurt the feet.

SUMMARY OF THE INVENTION Accordingly, it is an object of the inventionto provide im proved footwear having inner surfaces of a resilientmaterial formed to conform precisely to the contours of an individualwearer's feet.

It is another object of the invention to provide a novel method ofmanufacture of such footwear.

It is a further object of the invention to provide custom-fit footwearwhich can be opened to permit quick, easy entry of a wearers feet fromthe rear of the footwear.

It is yet another object of the invention to provide customfit footwearincluding durable outer members of standard size and custom-fit innermembers of a standard size insertable thereinto.

It is yet a further object of the invention to provide customfit membershaving resilient linings and replaceable inner soles and inner heels.

These and other objects of the invention are attained in a footweardesign which includes a foot encompassing member that may be of standardsize, having a resilient inner lining formed to conform precisely to thecontours of an individual wearers foot. The foot encompassing member isdivided, as into toe and heel sections, so that it can be opened topermit easy entry or removal of the wearers foot. If desired, a membercan be provided with removable inner soles and inner heels; the latterbeing divided to accept heel lifts of different sizes.

In a preferred embodiment of the invention, the foot encompassing membercomprises an inner shell of a boot, such as a ski boot, which alsoincludes a durable outer shell. The outer shell is of a standard sizeand the inner shell is of a corresponding standard size insertablethereinto. Both inner and outer shells are comprised of at least twocorresponding sections, such as toe and heel sections, which may becoordinately separated for easy entry and removal of the wearers foot.

In fabricating the foot encompassing members in accordance with theinvention, an unlined member of the proper size is selected for thewearer's foot. The stocking covered foot is placed within the unlinedmember, for example, comprising toe and heel sections of the inner shellof a ski boot. The foot encompassing member is retained in fixedrelationship to the wearer's foot, as by strapping the ski booth shellinto a pouring fixture; and liquid lining composition is injected intothe member to fill completely the voids around the wearers foot. In thecase of a ski boot, the liquid lining com position can be injectedthrough appropriate openings in the front and rear sections of the innershell by use of compressed air. After injection, the liquid liningcomposition is permitted to cure into a resilient semirigid state. Whenthe lining is cured, the foot retaining means are loosenedand thecustomfitted shell is removed from the wearer's foot.

If preferred, removable inner soles and inner heels can be fitted intoone embodiment of an unlined inner shell prior to injection of theliquid lining composition. Also, a stocking of polyethylene film orother suitable covering means can be provided on the wearer's foot toprevent the lining composition from adhering thereto.

BRIEF DESCRIPTION OF THE DRAWING These and other objects of theinvention will become apparent from the following detailed descriptionof the invention, taken in conjunction with the accompanying drawings,wherein:

FIG. 1 is a perspective view of a ski boot for a right foot constructedin accordance with the invention, shown in an open position;

FIG. 2 is a right elevation view, in section, of the ski boot shown inFIG. 1 when closed;

FIG. 3 is a partially exploded, right elevation view, in section, of theinner shell of the ski boot shown in FIG. 1;

FIG. 4 is an end elevation view of the front section of an altemativeembodiment of an inner shell of a ski boot;

FIG. 5 is a perspective view of an optional inner heel and heel liftarrangement utilized with the embodiment of FIG. 4;

FIG. 6 is a right elevation view in section of a pouring fixture used inthe installation of the liquid lining composition;

FIG. 7 is a top elevation view in section of the pouring fixture of FIG.6; and

FIG. 8 is a fragmentary sectional view taken along lines 8- 8 of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings onepreferred embodiment of the invention is described comprising a ski boothaving an outer shell and a custom-fit foot-encompassing inner shellinsertable thereinto. Both the inner and outer shells are divided intocorresponding front and rear sections so that they may be coordinatelyopened to permit easy entry of the wearer's foot.

Referring now to FIGS. 1-3, an outer shell 11 of a ski boot 10 for aright foot is shown, adapted to confine a line foot-encompassing innershell. The outer shell of the boot generally includes an upper 12 havinga cuff l4 and a sole 16 attached thereto. The boot is divided along theankle line of the upper and across the sole, as shown, to form a toesection 19 and a heel section 20. The toe and heel sections are securedtogether by a hinge member 22 of flexible material bonded across thedivided ankle line on a side of the boot. The hinge member permitspivotal movement of the toe and heel sections between the open positionshown in FIG. 1 and the closed position shown in FIG. 2. Sealing rings24, formed of rubber or other. suitable material, are provided along thecontacting edges of the toe and heel sections as shown in FIG. 8, toinsure a moisturetight seal when the outer shell is closed.

Conventional binding means are provided to retain the outer shell in theclosed position, comprising a clamp 27 provided on the toe section and acorresponding lug, not shown, attached to the outerv end of a strap 28bonded to the heel section. The clamp is adapted firmly to engage thelug to hold the shell closed, and can be released by the wearer so thatthe shell can be opened. Other conventional types of closures may alsobe used. Conventional binding posts 31, 32 are provided at the toe andheel of the outer shell, respectively to receive ski safety bindings.

A recess 30 is provided in the inner surface of the front of the toesection and similar recesses 33 are provided in the inner surface of therear of the heel section for a purpose to be described.

Cufi' 14 is adapted to wrap snugly around the ankle of the wearer and besecured in that position by conventional binding straps 35. The cuff ispreferably formed of molded urethane or some other resilient material.To insure a snug fit, the cuff is formed with ribbings 37 in the outersurface thereof to provide flexibility in the wrapping direction andstiffness in a direction transverse thereto. The out? may be constructedof other flexible materials, such as leather, which yield a producthaving the structural characteristics described above.

The outer shell of the boot is preferably fabricated of a molded plasticmaterial. Use of this material results in a lightweight durable, hardsurfaced product that can be produced in various colors. Furthermore,with the use of molded. plastic, the toe and heel sections of the outershell can be formed as integral units having extremely thin soles. Thispemiits placement of the wearers feet closer to the skis than waspreviously possible, and gives better ski control. The low profile bootsalso fit lower on the ankle than conventional boots and are morecomfortable to wear. However, it should be realized that other materialsused in conventional footwear, such as leather, metal and variousplastics, can be use in fabricating the footwear described herein.

Referring now to FIGS. 1-3, a finished, custom-fit inner shell of a skiboot for a right foot is shown. The inner shell is divided along theankle line in a manner similar to the outer shell to form a toe section41 and a heel section 42. These sections are designed to encompasssnugly the wearers foot when joined together. Accordingly, the toe andheel sections are provided with resilient inner linings adapted toconform precisely to the contours of the wearer's foot.

The toe and heel sections of the inner shell are also adapted to fitrespectively, within the toe and heel sections of the outer shell.Therefore, the inner shell is of a standard size corresponding to thestandard size of the outer shell and is adapted for a close tolerancefit therewith. The toe and heel sections of the inner shell are alsodesigned for coordinate movement with the corresponding elements of theouter shell as the boot is opened or closed. Accordingly, the sectionsof the inner shell are fabricated to fit completely within the sectionsof the outer shell with sufficicnt lengthwise tolerance that closure ofthe outer shell willcause the toe and heel sections of the inner shellto fit snugly about the wearers foot. Toe section 41 of the inner shellis provided with a locating boss 44, adapted to fit within recess 30 inthe toe section of the outer shell to insure proper registration betweenthose sections. If desired, the toe sections can be secured together bymeans such as screw 48, adapted to fit through a suitable opening 49 inthe outer toe section and engage a threaded nut 50 in the inner toesection.

In similar fashion, locating bosses 46 are provided on the heel sectionof the inner shell, adapted to mate with recesses 33 in the heelsectionof the outer shell. Fastening means such as screw 51 and nut 47 can beprovided to secure the heel sec' tions together in a manner similar tothe toe sections.

The inner shells can be fabricated of thin molded plastic and lined witha synthetic resin composition such as a liquid polyurethane composition,that has cured into a firm, resilient texture. The inner lining isinstalled by a method described hereinafter to conform precisely to thecontours of the wearers foot.

The inner shells can also be fabricated of other materials such asleather or synthetic materials. Likewise, other suitable materials canbe used for lining the inner shells provided the materials have thenecessary physical characteristics.

While the inner shells of the embodiment illustrated in FIGS. 1-3 arefabricated with integral soles, this is not required.

' Thus, referring to FIGS. 4 and 5, an alternative inner shellconstruction is illustrated that includes a removable inner sole 52'andinner heel 53. To accommodate the removable members, the bottomless toeand heel sections are fonned with lugs 54 depending inwardly from thebottom edges thereof. Corresponding grooves 55 are provided along theperiphery of the insertable inner sole and inner heel, adapted to engagelugs 54 and retain the sole and heel members in fixed position relativeto the wearers foot. As shown in FIG. 5, the inner heel can be dividedto accept heel lifts 56 of different sizes. This facilitates thelocation of a wearers foot at different desired angles with respect tothe ski depending on the particular type of skiing the wearer is engagedin. For example, high heels can be used for racing and low heels usedfor powder skiing.

The inner soles and inner heels can be constructed of con ventionalpadding material encased in a cover of leather or synthetic material.

In providing footwear having custom-fit linings an outer shell size isselected which is appropriate for the size of the wearers foot. Anunlined inner shell of a corresponding size and style is then selectedand if desired, fitted with inner soles, inner heels and heel lifts inaccordance with the wearer's needs. The wearers foot is covered with astocking of suitable weight and placedwithin the toe and heel sectionsof the inner shell, and the latter are retained together by suitablemeans such as-the pouring fixture shown in FIG. 6.

The pouring fixture includes a front member 60 recessed to receive thetoe section of the inner shell and including a holding strap 62 attachedthereto for securing the toe section to the base member. A rear basemember64 is also provided, being similarly recessed to receive the heelsection of the inner shell and including a holding strap 65 forretaining the heel section to the base member and in fixed relationshipto the toe section of the shell. Members 60 and 64 are designed to bead'- justably positioned and retained on a plate 66 by conventionalmeans not shown, so that theycan be used with several shell sizes. Whenthe wearers foot covered by stocking 69 is suitably located within theinner shell, a seal is provided between the top surface of the shell andthe wearers ankle, for example by wrapping a pad 68 around the ankle.This prevents the lining compound from escaping upwardly when placedwithin the shell. A liquid lining composition is then injected bycompressed air through suitable holes in the inner shell, until thevoids within the shell are completely filled. Such injection is carriedout by connecting the head of a container of catalyzed liningcomposition to an appropriate hole in the boot and applying air pressurefrom a suitable source to the base of the container. It is preferredthat the lining composition be inserted through a first hole in the toesection and a second hole in the heel section to insure gooddistribution of the composition. However, this is not required. Theliquid lining composition is such as to cure relatively rapidly into asemirigid state; after which the holding straps can be loosened and thecompleted custom-fit sections of the shell separated from the wearersfoot.

If desired, the customers foot can be encased in a polyethylene bag 70to prevent the lining composition from adhering thereto during thecustom-fitting operation. The bag can be provided with tabs 72 adaptedto extend through the joint between the toe and heel sections of theshell to prevent the front and rear sections of the lining from joiningtogether. Likewise, the inner soles when provided, can be covered withpolyethylene film during the lining operation to prevent the foam fromadhering thereto. Mandrels can be inserted into the inner shells inplace of the wearers feet during the lining operation, but such practicedoes not achieve as precise a fit as when an actual foot is employed.

The lining composition may be one of a number of known elastomericresins which can be catalyzed to a liquid foamed state and which willcure relatively rapidly to a satisfactory resilient form. One suchcomposition is polyurethane. The selected composition is preferablycatalyzed into the desired foamed condition shortly before introductioninto the inner shell. The composition is easily handled in the liquidstate and, when injected into the shell by compressed air, tends to flowreadily and completely fill the voids around the foot. Although thecuring time for such resinous compounds varies, it is usually of shortduration and does not subject the wearer to discomfort.

Various advantages result from use of the method described. For example,the method enables custom-fitting of footwear at the vending site with aprecision heretofore unattainable. Furthermore, the method enables thecustom-fitting of ski boots or similar footwear utilizing outer shellsof a limited number of standard sizes. For example, a manufacturer mightprovide three sizes to accommodate men, three sizes for women, and threesizes for children. Since the inner shells of the footwear areinterchangeable with any outer shell of corresponding size, a family ofgrowing children could all use the same set of outer boots, procuringonly their own individual set of custom-fit inner shells. Furthermore,if desired, the resilient linings might be removed from a set of innershells and the inner shells economically refitted for another wearer.Also, since the outer shells can be provided in a variety of colors, aperson might wish to own a single pair of inner shells usable with anyof a plurality of sets of outer shells of different colors.

In the embodiment illustrated the footwear is divided along the ankleline into distinct toe and heel sections. For the reasons mentioned,this is the preferred mode of construction. However, it is not required.Thus, it is within the scope of the invention to divide the footwearinto other configurations as long as suitable rigidity and ease of entryare maintained.

Furthermore, if desired, the inner shells can be singularly utilized asfootwear. Thus, in the case of ski boots, the inner shells can beprovided with satisfactory closures and suitably styled for use as afterski wear.

I claim:

1. An improved footwear comprising an outer shell including an uppermember and a sole secured thereto;

and an inner shell removably confined within said outer shell, saidinner shell having one relatively stiff wall in engagement with theouter shell and a resilient lining extending from said wall and customfit to conform precisely to the contours of a wearers foot.

2. An improved footwear comprising an upper member having a sole ofelongate dimension secured thereto, 7

said upper member being divided along the ankle line of a wearer andsaid sole being divided transverse to said elonelastomeric material intosaid foot encompassing m ns d. curing sard elastomenc material rnto aresilient rnner lrning which conforms precisely to the contours of thewearers foot.

4. A footwear as described in claim 1, wherein said outer shell isdivided into a plurality of sections and said inner shell is dividedinto a plurality of corresponding sections, the corresponding sectionsof said inner shell and said outer shell being coordinately movable foropening said footwear to permit entry and removal of the wearers foot.

5. Footwear as described in claim 2, wherein at least said upper memberincludes an outer shell and an inner shell confined within said outershell, said inner shell having a resilient lining which conforms to thecontours of the wearers foot.

6. Footwear as described in claim 5 further including flexible hingemeans secured to said upper member across the divided portion thereof. 7

7. Footwear as described in claim 5, wherein said sole includes a firstportion secured to the upper member of said outer shell and a secondportion secured to the upper member of said inner shell.

8. Footwear as described in claim 5, wherein said sole comprises a thinlayer of material secured to the upper portion of said outer shell andfurther including a resilient inner sole and a resilient inner heelremovably attached to the upper member of said inner shell.

, 9. Footwear as described in claim 5, further including alignment meansfor registering said inner shells with respect to said outer shells whenconfined therein.

10. Footwear as described in claim 4 further including flexible hingemeans secured between the plurality of sections of said outer shell.

1 l. Footwear as described in claim 4, wherein a second sole is securedto said inner shell.

12. Footwear as described in claim 11, wherein said second solecomprises a resilient inner sole and a resilient inner heel removablyattached to the upper member of said inner heel.

13. A method as described in claim 3 further including the step ofplacing a protective covering over the object before injection of thelining composition.

14. A method as described in claim 3 further including the steps ofplacing a stocking of polyurethane film having side tabs thereon overthe object and securing the tabs between the joint defined between thetoe and heel sections before injection of the lining composition.

1. An improved footwear comprising an outer shell including an uppermember and a sole secured thereto; and an inner shell removably confinedwithin said outer shell, said inner shell having one relatively stiffwall in engagement with the outer shell and a resilient lining extendingfrom said wall and custom fit to conform precisely to the contours of awearer''s foot.
 2. An improved footwear comprising an upper memberhaving a sole of elongate dimension secured thereto, said upper memberbeing divided along the ankle line of a wearer and said sole beingdivided transverse to said elongate dimension to permit opening of thefootwear; and means removably clamping the divided upper member anddivided sole in firm engagement encompassing the wearer''s foot.
 3. Amethod of forming improved custom-fit footwear comprising the steps ofa. selecting a foot encompassing member of standard size, said footencompassing member adapted to fit closely within an outer member ofsaid footwear comprising separate toe and heel sections, b. placing anobject having the dimensions of a wearer''s foot within said sections,c. injecting a liquid lining composition of catalyzed elastomericmaterial into said foot encompassing member, and d. curing saidelastomeric material into a resilient inner lining which conformsprecisely to the contours of the wearer''s foot.
 4. A footwear asdescribed in claim 1, wherein said outer shell is divided into aplurality of sections and said inner shell is divided into a pluralityof corresponding sections, the corresponding sections of said innershell and said outer shell being coordinately movable for opening saidfootwear to permit entry and removal of the wearer''s foot.
 5. Footwearas described in claim 2, wherein at least said upper member includes anouter shell and an inner shell confined within said outer shell, saidinner shell having a resilient lining which conforms to the contours ofthe wearer''s foot.
 6. Footwear as described in claim 5 furtherincluding flexible hinge means secured to said upper member across thedivided portion thereof.
 7. Footwear as described in claim 5, whereinsaid sole includes a first portion secured to the upper member of saidouter shell and a second portion secured to the upper member of saidinner shell.
 8. Footwear as described in claim 5, wherein said solecomprises a thin layer of material secured to the upper portion of saidouter shell and further including a resilient inner sole and a resilientinner heel removably attached to the upper member of said inner shell.9. Footwear as described in claim 5, further including alignment meansfor registering said inner shells with respect to said outer shells whenconfined therein.
 10. Footwear as described in claim 4 further includingflexible hinge means secured between the plurality of sections of saidouter shell.
 11. Footwear as described in claim 4, wherein a second soleis secured to said inner shell.
 12. Footwear as described in claim 11,wherein said second sole comprises a resilient inner sole and aresilient inner heel removablY attached to the upper member of saidinner heel.
 13. A method as described in claim 3 further including thestep of placing a protective covering over the object before injectionof the lining composition.
 14. A method as described in claim 3 furtherincluding the steps of placing a stocking of polyurethane film havingside tabs thereon over the object and securing the tabs between thejoint defined between the toe and heel sections before injection of thelining composition.